Alternating-current dynamo-electric machine.



B. Emmi-P. ALTEBMTLNG CURRENT DYNAMO ELECTRIC MACHINE.

APPLIOATIOII FILED HOV. 30,1906.

Pazezrfied June 22, 190

2 SHEETS-SHEET 1" B. ELSHOFP. ALTBRMTING 0111mm DYNAMO ELECTRIC mom. APPLIOA'I'IOH FILED NOV. 30,1905.

@535884' Patented June 22,1909.

2 SHEETS-rSHEET 2.

i 3 w M 31mins iggg a hurrah STATES rairaiur carrot BERNARD ELSHOFF, OF uoawoononro, ASS

IGNOR TO,ALLLSQHALMERSCOMPANY, A con- PQRATION or NEW JERSEY, AND THE BcLLooK E nc'rruc MANUFACTURING COMPANY,

A. QORPORATION OF OHIO.

Specification of Letters MACHINE.

Patented Julie 22,]19'091 l Application filed November 88, 1996.

.i '0 all whom it may concern: 4

Be it known that I, BERNARD ELsHorr, citizen of the United States,'residing at h orwood, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Alternating Current Dynamo-Electric Machines, of

which the following is a full, clear, and

exact'specification.

Qty invention relates to dynamo-electric machines and particularly to alternating.

in circuit with the secondary windings on starting, and to cut this resistance out gradually as the motor comes up to speed. In this manner the requirements'forbest starting and running conditions are fulfilled.

in some types of machines the starting resistance is arranged external to the rotor and is connected to the secondary windings.

by means of brushes bearing upon collector rings which are. carried by the rotor and are electrically connected to the secondary windings. In such machines, means are provided for short-circuiting the secondary windings aftenthe rotor is: up to speed.

This is usually accomplished by means of a short-circuiting switch arranged at the end I of the machine for connecting together-the collector rings.

In order that the resistance -.of the shortcircuiting' device may be as low possible it isnecessary that large contact. members he provided. in the short-circuiting' device and that the surfaces of contact be held very tightly. in engagement with one another,

T he movable contact member oftheshortcircuiting switch is usually controlled by .motor having end members ll and 12,

one 'or more levers extending outward from the end the machine: I Generally the actuating device is large, cumbersome, occupies considerable space and requires the expenditure of considerable manual energy to shift the short-circu-iting switch from one position to another. i

One of the objects of my invention is to 66 provide means for operating the short-cir cuit-ing switch and for obtaining adequate pressure between the movable and stationary contact members withoutrequiring the expenditure of as much energy as heretofore required.

A further object is to so construct and ar-' range th actuating mechanism of the short.- circuitii device that: the machine is con siderabl shortened and hence -'less floor 7 0 space required. i

My invention consists in novel details of construction and combinations and arrangements of parts described in'the specification and set forth in the appended claims. F or a better understanding of myinvenJ tion, reference is had to the accompanying, drawings in which' i Figure l is an elevation of an alternating current induction'motor equipped with my:

invention; Fig. 21s an enlarged section of the parts at the collector ring end of'the shaft showing the short-circuiting mechan; ism; Fig. 3 is a vertical section taken ap-, proximately along ,the line'3 ofFig. 2, 8'5 looking in the direction of the arrow; Fi 4 is a partial section taken along the line li of Fig. 2. looking ,in the direction of the arrow; and Fig. 5 is a'view similar to Fig. 2 showing a slight modification.

Referring now'to the figures of the draw-,

ing. 10 represents aLcasing of an induction vided with hearing housings for the shaft .13-

which,=carries the rotary member. I At'l/l, 15x95;

and 16 are shown three slip rings or collector rings. These rlngsfare secured, .by' n-:

sulated holts 17. to a ring. or collar 18 mounted on the end of the'shaft seas-u)- leave considerable space within the collector 1 010 rings. The collector rings are separated ii from one another and from the ring or 0.01131 4 I 18 by suitable insulation 19. '.,The portions, of the collector rings through which the separated from one another by radlal insu- .bolts 17 which clamp the collector rings to the boltsf17 so that said plate can be re- -moved without disturbing the other parts.

, members of the short-circuiting switch which 45 Y laminaemounted ona spool 33. The laminae means, such as bolts or rivets. The laminae ing piece may be integralwith the collar or Located ]ust beyond the collector ring 14 :f element' of the machine, each plate being y I :rings, in this case .by an insulated. bolt or screw 31 which passes through the flange 3O -plates 24, 25 and 26 and of the ring or I to thejplate 34 formingpartof the relatively movable member and to the bridging bolts 1' pass are slightly enlarged, as shown 1 at in Figs. 2,4 and 5, and each ring is 'also provided with aninwardly extending.

may be a separate piece secured thereto.

and separated. therefrom.by insulation '19 are three sector-shaped plates 24, and 26 lating partitions 27 Located on the outer side of the sector plates is' an insulating ring or washer 28 and beyond thering or washer is an end-plate 29. All these parts are tightly clamped together in this case by the the supporting ring 18. If desired however the end plate-29 may be secured in position by separate bolts or screws independently of .The plates 24, 25 and 26 are made of good conducting material and are each provlded with an inner flan e30 which is beveled on its-inner face. T ese plates form contact are fiied relatively to the shaft and rotary electrically connected to one of the collector of th'e plate and the inwardly extending lug 21 of the ring. The central portions of the opening. 7 I v Therelatively movable contact member. of

washer 28 are cut away forming a circular .the short-.circuiting switch is shown at,32

and consists of a group of disk-shaped are clamped together and to a plate 34 on one side of the laminae by any suitable are of gradually increasing diameters so as to form a beveled surface which may be clamped against the beveled flanges 30 of the relatively stationary contact members. The actuating or operating means for the short circuiting switch consists in this case of two sets of'to gle arn1s'35 located entirely within the'col ector rings, the arms being pivoted cross piece 23. Y I

Inithe "referred"form*of my invention shown in ig. 2, each pair of toggle arms is provided with a roller 35 mounted on the pin connecting the two arms. It is seen that when the toggle arms are straightened out or cramped the movable switch member is moved outward and is forced into engagement with the contact plates 24, 25 and 26.

Pressure is applied to the toggle joints by means of an axially movable arm or rod 36 having in this case a collar 37 within the collector rings which collar is provided with-5a ,beveled or conicalportion 37 iTlTCl a cylindrical portion 37". The operating arm 36 is supported by the bridging member 23 and by the end plate 29 which are provided with suitable openings directly in line with the axis of the shaft. The arm is provided at its outer end-with a hand piece 38 by means of which it can be moved in or out. The arm is also preferably provided with a collar 39 between the end plate 29 and the movable switch member 32 to engage the latter so as to insure the switch being opened when the arm 36 is moved inward. I haveprovided positive stops for the inner and outer positions of the arm 36, consisting in this case of a member'40, preferably a ball, pressed inward against the arm 36 by a spring 41. The ball and spring are located in a socket or recess in an outer lug or extension of the end plate 29, being held therein by a screw 42. The arm 36 is provided with grooves 43 and 44 so located as to receive the ball when the arm has reached its inner and outer positions respectively.

- It is seen-th'atwhen the arm 36 is pulled outward the rollers 35 ride up on the conical portion 37? of the collar 37 and then on to the cylindrical vportion 37 The arms are thus spread outward, forcing the movable switch member tightly into engagement with the relatively stationaryv switch members. It will also be seen that comparatively little pressure applied to the toggle joints causes a very great pressureat the outer ends of the toggle arms or between the contact faces of the switch. The action of centrifugal force tends to .close the switch, thus lessening the energy necessary to be expended by the operator in short circuiting the windings. Furthermore centrifugal force assists in lmaintai'ning the switch closed so that there is little danger of the windings being opencircuited during the operation of the machine. When the switch isv closed, since the rollers rest on the cylindrical portion 37 of the collar, there is no tendency for it to open. Inthis position of the arm the ball 40 lies in the groove 44 and prevents the switch being accidentally opened. To open the a switch the arm 36 is pushed inward, permitting the rollers 35 =to ride down the beveled portion 37Hof the collar 37 The switch member 32 is then engaged by the collar 39,

positively forcingtheformer away from the contact plates in case for any reason the switch should not open when the 'arm 36 is pushed inward. It is seen also that the actuating mechanism is located entirelv within is closed the links 45 are almost in a line so that there is little tendency for the switch to open due to the pressure between the contact faces of the switch. The arm 36 be provided on each side of the bridging piece 23 with means such as collars 46 and 47 to prevent excessive movements of the arm 36.

It is evident that my invention may be modified considerably in the minor details without departing from its spirit and scope and I aim in my claims to cover all such modifications.

What I claim as new and desire to by Letters Patent is I. In an alternating current motor, a plurality of collector rings,'n1eans for shortcircuiting said rings comprising contacts fixed relative to the. rings and conductively related thereto, an axially movable contact adapted to engage said relatively fixed consecure tacts, and means for shifting the axially movable contact. comprising a toggle mechanism connected thereto and located within the rings, and a manually movable device in operative relation to the toggle mechanism.

2. In an alternating current motor, a shaft, a plurality of collector rings, a short cir cuiting device therefor comprising a plurality of contact members fixed relative to the rings and conductively related thereto. and a contact member movable with respect to the rings, and adapted to engage the relatively fixed contact members, a toggle mechanism forshifting said movable contact member, and-an axially movable rod in line with the center of the shaft and in operative relation to the toggle mechanism for controlling the latter.

In an alternating current motor, a shaft, a plurality of collector rings, means for short circuiting said rings comprising contact members electrically connected to the rings and fixed relative thereto. a contact member movable relative to the rings, a toggle mechanism for forcing said relatively movable contact member into engagement with the relatively fixed contact members,

said toggle mechanism being located within the rings, and means for actuating the toggle mechanism comprising a longitudlnally movmay able rod in line with the center of the shaft and in operative relation to the toggle mechamsm.

l. In an alternating current motor, a plurality of collector rings. a short circuiting device therefor comprisii'ig a plurality of contact members fixed relative to the rings and conductively related thereto, and an axially movable contact member, a toggle mechanism for shifting said axially movable contact member. and an axially and longitudinally movable rod in operative relation to the toggle mechanism for controlling the latter.

In an alternating current motor, a shaft, a plurality of collector rings, and means for short circuiting said rings comprising contact members fixed relative to the rings and connected thereto, and a cooperating axially movable contact member. a toggle mechanism connected to said axially movable contact member, and a longitudinally movable rod passing loosely through said axially movable contact member, in line with the center of the slmft, and in operative relation to the toggle mechanism.

6. In an alternating current motor. a shaft, :1 pluralityof collector rings, and means for short circuiting said rings, comprising a plurality of contact members fixed relative to the rings and connected thereto, and a cooperating axially movable contact member located beyond the end of the shaft and within said rings, a toggle mechanism also located within the rings and connected.to said axially mo able member. and an axially movable rod in operative relation to the toggle mechanism, said rod being supported beyond the end of the center thereof and passing loosely through said axially movablecontact member.

7. In an alternating current motor, a shaft, a plurality of collector rings. means for short circuiting said rings comprising contact members fixed relative to the rings and connected thereto and a cooperating axially movable contact member. a toggle mechanism connected to said axially movable contact member, and a longitudinally movable rod in operative relation to the toggle mechanism and supported in line with the center of the shaft, said axially movable contact member being slidably mounted on said rod.

In testimony whereof I aflix my signature, in the presence of two witnesses.

BERNARD ELSHOFF.

Vitnesses A. F. Kwis, FRED J. KIxsEY.

shaft in line with the 

